PHILADELPHIA — The Eagles showed Sunday that Chip Kelly’s hurry-up offense can win in any kind of weather.

Of course, it doesn’t hurt to have LeSean McCoy, too.

With McCoy leading the way, Philadelphia eventually shook off the blizzard-like conditions and stayed atop the NFC East by sprinting to a 34-20 victory over the stunned, mistake-prone Lions at frosty Lincoln Financial Field.

McCoy broke Hall of Famer Steve Van Buren’s 64-year-old single game franchise record by rushing for 217 yards and two touchdowns on 29 carries, with almost all of it coming in an inexplicable fourth quarter in which the Eagles improved to 8-5 by outscoring Detroit 28-6.

“It was the worst game I’ve ever played in, weather-wise,” McCoy said of the blinding snow that collected in thick piles between the yard lines until finally letting up in the second half. “It was my best one, too.”

Incredibly, the Lions led this one 14-0 midway through the third quarter before melting down in the face of a ferocious Philly ground assault led by McCoy that pounded out 299 yards. Detroit’s defense had allowed 243 rushing yards in its previous six games combined.

The rushing heroics of McCoy and to a much lesser extent backups Chris Polk and Bryce Brown enabled the Eagles — who trailed 8-0 at halftime — to score TDs on five of their final six possessions.

And it would have been a perfect six-for-six if tight end Brent Celek hadn’t taken a wide-open pass from Nick Foles and slid just short of the end zone to run out the clock instead of going in for the easy score.

“Everybody got used to the snow after the first half, and that really helped us,” Eagles center Jason Kelce said. “The snow also slowed down and then stopped, pretty much, so you could actually see. It didn’t feel quite as slick, either, so you could grab the ball. All of that made a difference.”

The bumbling Lions gave the Eagles a big assist, too, fumbling seven times (losing three of them) and generally looking the part of a dome team playing in mounds of snow once they took a 14-0 lead.

The conditions hampered Detroit even before the opening kickoff. Running back Reggie Bush, who would have been an asset in conditions that made throwing the ball frightful and kicking it impossible, slipped in warmups and ended up not playing at all after aggravating a quadriceps injury during his fall.

Joique Bell rushed for 69 yards in Bush’s absence, but the Lions — with their potent passing game essentially nullified by the snow — couldn’t do much right on either side of the ball once McCoy started the Philly avalanche in the third quarter.

The loss was costly for the Lions, too, dropping them to 7-6 and possibly into a tie with the Bears atop the NFC North if Chicago upends the Cowboys Monday night.

“Pretty much, we didn’t make any tackles in the second half,” Lions cornerback Chris Houston said. “I don’t really know what was going on with that.”

Even textbook tackling technique probably wouldn’t have mattered much against McCoy, whose trademark shiftiness wasn’t hampered by the snow at all in the second half.

There’s no telling how many ankles McCoy broke among Detroit defenders on TD runs of 40 and 57 yards in the fourth quarter that ended up giving the Eagles the lead for good.

There was no need for another near-perfect day from Foles (whose season-long streak of having thrown no interceptions was finally broken Sunday) when the Eagles had McCoy.

“I can usually plant on a dime, but sometimes I couldn’t really plant today,” McCoy said. “But it all worked out.”